Automatic alarm and shut-off for steam boilers



July 5,1927. 1,634,392

J. BARRETT AUTOMATIC ALARM AND SHUT-OFF FORSI EAM BOILERS Filed Feb. 27, 1922 2 Sheets-Sheet l A T Tale/V255 July 5,1927. 1,634,392

J. M. BARRETT AUTOMATIC ALARM AND SHUT-OFF FOR STEAM BOILERS Filed Feb. 27, 1922 2 Sheets-Sheet 2 Patented July 5, 1927.

UNITED STATES PATENT OFFIOE.

JOSEPH M. BARRETT, OF FOSTORIA, OHIO, A$SIGNOR TO THE S41 REGULATOR MANUFACTURING COMPANY,

OF FOSTORIA, OHIO, A CORPORATION OF OHIO.

AUTOMATIC ALARM AND SHUT-OFF FOR STEAM BOILERS.

Application filed February'z'i, 1922. Serial No. 539,790.

This invention relates to attachments for steam boilers for automatically giving an alarm in case of the water falling to a dangerous level. It also eomprehends means, which may be employed when fluid fuel is used, for shutting off such fuel when such dangerous condition arises, thus maintaining the boiler in safe working condition.

In operating boilers, particularly in isolated locations, such as oil fields, wherein one operator is employed for maintaining a number of such boilers in condition, it sometimes happens that the boiler feed water apparatus is impaired and that the boilers are burned out before the operator is apprised of the situation in time to prevent the boiler from being damaged. Considerable difliculty has been experienced in obtaining an alarm which is positive in its operation, and which is adapted to be readily attached to existing boilers.

Accordingly one of the objects of my invention is the provision of means which is adapted to be readily attached to existing boilers and employed for giving an eliective alarm whenever low water occurs. In addition, my invention contemplates the inclusion of a warning signal to an operator who may be at apoint remote from the boiler, together with suitable mechanism (employed if desired) for indicating at a separate control station the particular boiler requiring attention. I so arranged .the alarms that once placed in operation they are caused to remain in action, until an operator arrives at the boiler and manually releases the alarm actuating mechanism.

When my alarm is employed with a boiler having oil or gas .fuel, I combine it with a valve arranged to .shut oil the fuel by the same operation which actuates the alarm.

The means for accomplishing the above objects will be more fully set forth in the following description which relates to the drawings, and the essential characteristics of my invention will be summarized claims. 7

Fig. 1 is an end elevation of a boiler showing portions of a control mechanism embodying my invention; Fig. 2 is a side elevation of a portion of the boiler show- .ing a valve control means actuated bythe mechanism illustrated in Fig. 1; Fig. 3 is an elevation of a diaphragm operated valve showing signal actuating mechanism with the in the fuel valve in open position; Fig. 4C is an ele- .vation of the mechanism shown in Fig. 3

with the valve stem in closed position; Figs.

5 and 6 are sections taken on the lines of 55 and 6-6 respectively in Fig. 3.

In the various figures, 10 indicates aboiler having a feed water line 11 and fuel line 12 adjacent the bottom thereof, and having con nections 13 and 14 respectively above and below the normal water line. Intermediate the connections 13 and 1 1 I have shown a pressure control generator 15 which communicates through a tubular passageway 16 with a spring opera-ted diaphragm valve 17 in the teed-water line. The generator 15 is mount- .ed on a conduit 18 whichmay beformed of several lengths of pipe fitted together and secured to the connections 18 and 14, thus tormin g a, closed circuitor bypass, the lower portion of which is filled with water, and the upper portion with steam. A suitable blow-oil conduit 20 having a valve 19 therein may be connected with the conduit 14.

The generator 15 comprises a secondary pressure chamber which depends for its operation on the dill'erence in temperature between the steam and water within the conduit 18, and which is set to control the valve 1'4", thus insuring a steady flow of water to the boiler. I have shown my invention as embodying a generator 21 which is similar in construction to the generator 15, and which is adapted to communicate with one end of the conduit 22. The other end of such conduit terminates in a chamber 23 on one side of a diaphragm 24-, whichtorms a part of a signalcontrol systein as will be hereinafter described.

The construction of the generator shown is set forth and claimed in Patent No. 1,193,- 124, issued to N. G. Copley on August 1, 1916, but for purposesof identification of this invention, it is sufficient to state that the generator 21 is positioned below the normal water level, but above the bottom of the boiler, so as to insure tree passage of water through the connection 14:. Under normal conditions then, the generator 21 entirely l middle points 37 and in the form of oil or gas and is conveyed to the boiler through the conduit 12. Accordingly l have provided in such conduit a valve 26, which is directly connected to a stem 27, and whichis adapted to be actuated by the spring 25. VJhile the boiler is in operation, the valve is maintained in open position, as shown in Fig. 3, wherein the spring is compressed.

The mechanism for controlling the alarms, comprises a diaphragm plate carried by a spindle 31 which is slidably mounted in a standard 32; this plate abuts the diaphragm 24 and is held thereagainst by spring 25 so that under normal operating conditions, the force of such spring is greater than the pressure within the chamber 23 on the opposite side of the diaphragm.

The means employed for connecting the spindle to the spring may include a yoke 33 which is pivoted at 34 to the spindle 31, and which is provided with an extension piece 35, the outer end of which terminates in a 'lznob 36. The opposite faces of the yoke may then provide pivotal supports, as at 37, and '33, for the links 39 and 40, respectively. The outer ends of the links or arms 39 are pivoted to the standard 32 at 41 wiile the outer ends of the links are pivotally connected to the spring plate 43, as at 42. The links 39 and 40 thereby form a toggle joint which transmits lateral motion of the spindle 31 to vertical motion of the spindle 27, which latter actuates the alarm signal.

The spindle 2'? extends through the spring 25 and is supported for longitudinal move ment in a transverse member 44, which con stitutes part of the standard 32. The upper most end of this spindle may terminate in a bifurcated portion as at 45 to receive a lever 46 which is pivoted at 47 to the stand-- ard 32. This lever as shown in Fig. 2 may be so connected through a suitable member 48 to an operating lever 49 of a whistle 50, that a downward movement of the lever 46 actuates such whistle.

he lever 46 is moved downwardly whenever the spindle is longitudinally moved a predetermined amount. In other words, when the water level within the boiler is above the generator 21, the pressure in the chamber 23 is not suflicient to overcome the force of the'spring 25, and accordingly the plate 30 is held against the diaphragm with the middle points 3'? and 38 of the toggle joint, on that side of the center line adjacent the diaphragm.

If for any reason the water level within the boiler should drop until it is 011 a level with the generator 21, then the steam adjacent the generator 21 raises the temperature and hence the pressure therein until the force of thespring 25 is overcome. Thereupon the spindle 31 is moved longitudinally until. the 38 of the toggle joint are urged toward the center of the 27. A further increase of pressure generator moves the points 37 and 38 beyond the center line of the spindle 27, where upon the force of the spring 25 is expended in throwing the toggle links to the position shown in Fig. 4 and carrying the spindle 27 downwardly, thereby closing the fuel valve 26 and also actuating the alarm, as, for instance, the whistle 50.

When the whistle is actuated, an operator at a remote point is immediately apprised of the location wherein trouble is imminent, the generator 21 being so positioned that suflicient time will be allowed to enable the operator to reach the boiler before any actual damage occurs.

An additional precautionary measure, howspindle in the ever, is to utilize an electric alarm which is also adapted to be actuated by a downward movement of the stem 2'2. This alarm may comprise an audible or visible or combined signal 60, at a point remote from the boiler, and preferably at a central control station. Inthis station, an indicator system may be used for apprising one of "the exactboiler requiring attention.

In Figs. 2 and 3, l have shown an electric signal as having a source of power 61, with leads 62 and 63, which terminate in the con.- tact plates 64 and 65 on the standard 32, and spindle 2'? respectively. In 3 the contact plates are shown in separated position while in Fig. 4 such plates are in engagement.

A ter the operation of'the low water signals is initiated, then such signals will continue in operation so long as steam remains in the boiler, or the source of electric supply remains. This condition occurs by reason of the fact that the spring, when once extended, holds the toggle joint in the position shown in Fig. 4. Accordingly, to re-set the alarm, it is necessary to manually force the yoke 33 inwardly against the tension of thespring 25, thus bringing the plate 30 into contact with the diaphragm, and the points 37 and 38 on the center line, as shown in Fig. 3.

The generator 21 is shown as surrounding the conduit 18 and as positioned intermediate the generator 15 and the connection 14. This center conduit therefore, serves as a fluid passageway for actuating the feed water control mechanism, and for operating the alarm apparatus. An advantage of suchan arrangement is that the generator for the alarm apparatus may be readily installed on boilers equipped with feed water control mechanism, operating on the thermostatic principle, without cutting the boiler for additional connections. However, if desired, each generator may have its boiler connections independent of the other. I

While I have explained my invention as other side of the having a valve which is adapted to shut off the fuel, it is understood that it may also be satisfactorily employed in coal biu'ning furnaces without destroying the effectiveness of the signal system as controlled indirectly by the water level falling below a predetermined amount. in such cases the valve 26, together with the valve body, may be eliminated, and the bottom of the standard 32 may be secured to a bracket (not shown) mounted on the boiler wall. The valve, when employed, and either of the signals, whether the valve be employed or not, constitutes an emergency device normally inactive but effective upon low water occur ring.

From the foregoing description it will be seen that I have provided a low water alarm apparatus which is positive in its operation, and which is well adapted for use in connection with the operation of boilers that are separated a considerable distance from each other, thus enabling one operator to tend to a number of such installations without endangering the boilers.

Having thus described my invention, 1 claim:

1. The combination of a fluid fuel intake pipe leading to a boiler, a valve in said pipe a valve actuating rod extending therefrom, a frame mounted on the valve longitudinally embracing the valve actuating rod, alarm means associated with the rod and frame, a spring within the frame fixed at one end to the frame remote from the valve, and at the other end to the middle of the rod tending to normally force the rod into the valve chamber to close the valve, a toggle loosely fixed at one end to the frame opposite the spring and near the valve and at the other end to the rod adjacent the connection of the rod and spring with the three toggle pivot points but slightly out of alignment with the rod, a lever extending transversely of the frame being limited in travel within the frame and adapted to bemanually operated exteriorly of the frame and loosely connected to the middle pivot of the toggle at its mid-point and connected to a second rod at the other end, a diaphragm associated with the second rod supported at the side of tie frame, a pressure chamber enclosed on one side by the diaphragm, so that the diaphragm reacts on the second rod thence on the middle toggle pivot throwing the tog gle past center allowing the spring to force the rod into the valve chamber thereby closing the valve and actuating the alarm means.

2. The combination of a fluid fuel line leading to a boiler, a valve in said line, a valve actuating rod extending from the wive chamber, a frame mounted on the valve extending longitudinally of the valve actuating rod and supporting said diaphragm, a plunger associated with the diaphra; n extending into the frame adapted to be forced into the frame responsive to pressure exerted on the diaphragm, a togpivotally con ected to the frame and to the valve actuating rod and extending along the rod, resilient means connected to the frame and rod tending to collapse the toggle ind force the rod into the valve chamber, a 'ver transverse the frame pivotally connect- (l to the plunger and to the middle pivot of he toggle, means associated with the lever ,dapted to abut the frame and limit the motion. thereof, said lever extending without the frame and adapted to be manually operated, the motion of the lever being so limited tiiat the middle pivot of the toggle is but slightly out of alignment when the valve is open and adapted to be forced past center by pressure on the plunger and further forced beyond alignment as the resilient means forces the rod into the valve chamher, and alarm means associated with the rod and frame to be actuated as the .rod is forced into the valve chamber and to remain active until the rod is again lifted by operating the above named lever manually.

in testimony whereof, I hereunto allix my signature.

J. M. BARRETT. 

